Text capture: Difference between revisions

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===tvtime support for closed captioning===
===tvtime support for closed captioning===


tvtime has built-in support for closed captioning for bttv and saa7134 cards (also other?).
tvtime has built-in support for closed captioning for [[bttv devices | bttv]] and [[saa7134 devices | saa7134]] cards (also other?).


In early 2004, Kevin Ko wrote a [http://www.princeton.edu/~kko/tvtime/vbi_lock_0.2.patch patch with useful comments] to tvtime's vbidata.c; see [http://www.princeton.edu/~kko/tvtime/ his detailed account] and [https://sourceforge.net/tracker/?func=detail&atid=506989&aid=884449&group_id=64301 the tvtime bugreport].
In early 2004, Kevin Ko wrote a [http://www.princeton.edu/~kko/tvtime/vbi_lock_0.2.patch patch with useful comments] to tvtime's vbidata.c; see [http://www.princeton.edu/~kko/tvtime/ his detailed account] and [https://sourceforge.net/tracker/?func=detail&atid=506989&aid=884449&group_id=64301 the tvtime bugreport].



===Unsupported cards===
===Unsupported cards===

Revision as of 06:52, 22 April 2005

The PAL standard uses teletext, while the NTSC standard uses closed captioning. The various television capture chips implement these technologies in different ways.


Applications


ntsc-cc

The application ntsc-cc handles closed captioning on bttv devices. For ntsc-cc to work, you typically need to be running an application for viewing or recording television, such as xawtv and mencoder. If no such application is running, ntsc-cc tends to produce garbled output.

tvtime support for closed captioning

tvtime has built-in support for closed captioning for bttv and saa7134 cards (also other?).

In early 2004, Kevin Ko wrote a patch with useful comments to tvtime's vbidata.c; see his detailed account and the tvtime bugreport.

Unsupported cards

There is currently no code supporting closed captioning on cx88 cards.